Greetings - I have a 1997 Volvo 850 Turbo Sedan.

There is a "whirring" noise coming from under the hood. It sounds like a "high idle" noise. Today - the noise took on a scaping or grinding sound in addition to the "whirring" noise.

It doesn't seem to happen in connection to any one thing. Happens when I'm in park with the car running, happens when I'm on the road driving.....doesn't seem to be any rymn or reason to when or why.

I have made an appt with the Volvo dealership to get it fixed - but I would REALLY like to know more about a possible cause before I go in. I HATE going in "stupid".

Anyone know what might be causing this?

ok...


is it running smooth

get it idling..open up hood, does it sound as if its coming from directly in the block or not (check your oil levels)


is it running at a higher temp than usual?


first thoughts are blower motor (whiring) or water pump (grinding) although water pump may whir too i imagine.

possibly the blower motor went bad then the excess stress on water pump made it go bad explain the whirring only first and then the grinding.


just some ideas


sean

I have a '95 850 non turbo. I have (i think) what you would call a whirring noise that has been diagnosed by the dealer I purchased it from as a stuck/frozen belt tensioner. Maybe the same problem you are having?

yes i suppose this could also be the problem....

neo...did your noise not change frequency in relation to the engine speed.

i only mention this as kathva said its no seemingly related to engine speed/car speed, pumps etc would not relate to any of this, where as i would have thought that a belt tensioner on the timing belt would produce different pitches at different rpms.
im not trying by anymeans to disregard your post...just offering my thoughts.


sean

Correct Sean - the "whirring noise" does not change in pitch of frequency depending on acceleration. I also made note of numbers on the Tac - and that does not change when the noise kicks in or goes away.

I haven't noted a change in temp - I'm pretty good about watching that.

I'm going to go now and open the hood and let it run so I can tell where the sound is coming from exactly.

I'll let you all know what I find. Thanks for the thoughts everyone - keep em coming.

check oil levels whilst your out there

Oil levels are good. I have the oil changed every 3k-4k miles and they are consistantly good - full.

I just had the hood open and the car running for about 20 minutes. Of course - didn't happen. I'll keep listening with the hood open. The only thing I heard was a fan kick on - sounded like the radiator fan....

fan is normal especially if idling as no air is passing through (from the car moving) so the fan needs to pass the air in the same way as if the car was moving (nothing to worry about)


good luck finding the noise

Look at the belting areas. Specially the variable belt.

OK - Still hoping to be able to open the hood when it happens and ID the source of the noise. I've been "on the road and enroute" when it has happened today.

But I've started keeping very close track of when.... here's the data so far today:

Today - happened twice - each time, after the car had been sitting for more than 8 hours (morning and after work). Happened once I started the car, put it in drive and drove about 1-2 minutes. Lasted only about 15 seconds this morning - lasted about 30-60 seconds after work.

Tomorrow - I hope to orchestrate it so that I'm in a position to be able to stop and open the hood when it happens. Stay tuned.

Kathleen

hmmm sounds like something with the cooling systems to me...as per my original posts
just because its not something thats not constant and when it does happen it only happens for a short period of time. and the sounds your describing i would associate with the parts i mentioned earlier. although you said it diddnt happen when the fan came on whilst idling. so im abit confused.

anyone else think of any systems that come on temporarily?

sean

The variable belt powers the compressor for the airconditioning. As such, if its worn, and you switch on the airconditioning, you stress the v-belt more, hence the noise.

My 2 cents.

Hello everyone, My first thought of "high-idle whineing noise" would be the obvious things everyone has mentioned like belts, tensioner, waterpump, AC compressor but they generally give noise all the time when there is a problem. How about the bearings on the turbo ? No oil delivery upon cold start-up. I have had a couple of turbo's whine and squeel pretty good! Mostly upon cold start-up with low oil level though. What grade of motor oil have you used and what kind of temperature are we looking at for start-up?

it might be the power steering. i've had that noise and it took me like several months before someone suggested it. mine went away once the car was warmed up. it was worse when it was cold and humid out. got a used one from the junk yard and replaced it. found it was that and then bought a new one and sold the old one on ebay. even money. woooooohooooooooooooo. just another suggestion from your psycho moderator. :grin:

Bearings on A/C compressor starting to go?

When the A/C compressor bearings start to pack up, they sound a bit like a CV joint on the way out.

A/C starting to go thats what I heard a click then a humming noise ...Bearing...........Be real careful but start the engine and get a long srewdriver and put the driver on the AC compresser and plug the handle of screw driver in your ear and you will hear if a bearings going ..if your driver get trapped in your belt the last thing you will see is your AC real close up

I use an old telescopic car radio aerial with the bottom end of it plugged into the tube of an old stethoscope headpiece (my son's a surgeon).

You can put this contraption in and around the engine and you don't have to worry about it coming back at you at a great rate of knots.

Keep in mind your head is on the side with the screwdriver poked in your ear and therefore it's basically impossible for you to keep an eye on the tip of the driver to ensure if it's in the exact spot you want it to be.

It could easily slip and hit a rotating pulley or belt, then bingo.

It's alright to have a grin from ear to ear, but a screwdriver from ear to ear - not a good look.

I hope he has started with something...
:)

After spending a bit more time thinking about your problem, I'm wondering whether your problem is coming from A/C fans.

I'm assuming your '97 Turbo has an Electronic Climate Control (ECC) A/C system.

If the A/C system is set in the 'auto' mode, various duct fans plus the coolant fan will start and stop as required after receiving appropriate signals from the ECC unit in conjunction with the engine Electronic Control Unit (ECU).

If any fan(s) have a 'dry bearing' then the fan will give off a muted screeching or 'tortured' sound caused by friction between the two metal bearing surfaces of the shaft bearing and the rotating shaft which attempt to 'bind' due to lack of sufficient lubrication.

Your car could have an Air Pump / Smog Pump to if it does it would be on the driver side under / behind the battery.